The President of the European Parliament has justified filtering 457,325 protest emails sent to Members of the European Parliament (MEPs) -- 106,771 of them from the same address -- as necessary in order to ensure the functioning of the Parliament's email services.

Pirate Party MEP Christian EngstrAPm complained to the President last month after the Parliament's IT department blocked emails relating to a report, "Eliminating gender stereotypes," that the Women's Rights and Gender Equality Committee was due to present to Parliament. The emails were protesting a ban on online porn that the report was expected to propose.

In the report, the committee asked the European Commission to consider drawing up legislation to eliminate gender stereotyping in the European Union. Parliament approved the report, but not before controversial parts of the text were dropped. Point 17 originally called for a ban on all forms of pornography in the media and on the advertising of sex tourism. This proposed ban included the Internet, according to civil liberty groups. The line was ultimately deleted from the report.

While the proposed ban on online porn was always unlikely to pass, digital rights group EDRI and Pirate Party founder Rick Falkvinge asked civil liberties advocates to lobby their MEPs. This resulted in MEPs' inboxes being swampedA with emails protesting the report, prompting the Parliament's IT service to install a filter.

EngstrAPm wrote to European Parliament President Martin Schulz about a month ago to complain about the filter, saying that deliberately blocking emails from genuine citizens wishing to contact their elected representatives was completely unacceptable.

The problem, according to figures provided by Schulz in a reply published by EngstrAPm on Monday, is that those sending the emails were not just contacting their own elected representative, but all of them.

In total, 708,683 messages concerning the report were received from 850 different email addresses, averaging 800 emails per address, Schulz wrote. "One single email address was responsible for sending 106,771 emails to the European Parliament," he said, with the number of mails sent to the Parliament about the topic reached 500 emails per minute at one point, most of them coming from two main servers.

In order to guarantee the functionality of the European Parliament's email system, one of the essential services offered to the Parliament, it was decided to install a filter to reduce the number of external emails relating to the report on "Eliminating gender stereotypes," wrote Schulz . The filter blocked 457,325 such messages, and 251,358 were delivered, Schulz said.

"Considering that the European Parliament receives on average 250,000 emails from external senders per day and that in addition 230,000 emails concerning the report on 'Eliminating gender stereotypes' were received, this is a strong indication that the European Parliament is being targeted by mass emails," Schulz said.

Considering the high number of emails received in a very short period of time, the limited number of related email accounts used to sent those mails and because emails were sent automated, the intervention of the technical services was justified, Schulz said. No emails were deleted, the blocked mails have been stored in the quarantine part of the infrastructure, Schulz added.

"In his answer, the President of the European Parliament defends the blocking of the emails from citizens to MEPs as spam, and does not in any way indicate that he will do anything to prevent this from happening again. I find this completely unacceptable," said EngstrAPm in a blog post.

If 850 European citizens mail each of the 754 MEPs this will result in several hundred thousand emails being sent, EngstrAPm wrote. "But that is no justification for the administration of the European Parliament to take the decision to censor those citizens by just silently discarding the emails that citizens send, so that they do not reach the elected members," he said, adding that in his opinion citizens who make there voices heard are an asset to the political system and not a problem that needs to be addressed by spam filter.

But mailing all MEPs at once might not be the most effective way to protest, said Myfanwy Nixon, marketing and communications manager for mySociety, a U.K. nonprofit organization that runs WriteToThem, a website that allows people to contact elected representatives, from local councils to the European Parliament level.

"Throughout the site's existence, we have heard many times from MPs and other representatives that bulk emails are at best an irritant and at worst bring down systems, preventing important work from being done," she said. Rather than sending a preformulated response, as people were asked to do in the antiporn ban protest, the organization believes that when protesters take the time to compose their own email, with their own experiences or thoughts woven in, it is far more likely to have an effect, she said.

"Typically, a U.K. resident is represented by 5 MEPs, and WriteToThem does allow a user to contact all of them -- however, we do not allow contact with every MEP," she said.

If mySociety would allow that, the service would probably be used by professional lobbyists in the same way as marketers send spam to as many people as they can, according to the organization. Eventually, representatives would ignoreA everyA message sent through the service, instead of trusting it as a source of letters from constituents, it said.

"And the main losers in this would be real constituents with real problems," according to mySociety.

Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com